东北地区玉米生长发育特征及其对热量的响应

Maize growth and its responses to heat condition in Northeast China

在大田条件下,以3个玉米品种(丹玉39、原单29和龙单13)为试验材料,设置早、中、晚3个播种期,分析了2007—2008年不同播期3个玉米品种关键生育阶段特征及其对温度的响应.结果表明:从播种到出苗所需天数依次为早播(平均值为13d)>中播(平均值为11d)>晚播(平均值为8d);出苗阶段平均气温在18℃左右时的出苗速率最快,气温偏高或偏低都会降低出苗速率.3个玉米品种在苗期营养阶段生育期天数的差异不大且受温度影响较小;从穗期阶段开始,晚熟品种龙单13的生长速率提高,成熟天数明显缩短;3个品种在穗期和花粒期阶段生长天数均随温度的增加呈减少趋势.全生育期地上干物质积累速率、产量、百粒重均表现为丹玉39>原单29>龙单13.

Taking 3 maize cuhivars （Danyu 39, Yuandan 29, and Longdan 13） as test materials, a field experiment was conducted to study their growth characteristics and responses to air temperature under the conditions of early, medium and late sowing. For the three cultivars, the days from sowing to seedling emergence under early, medium and late sowing were averagely 13, 11 and 8 d, respectively, and the seedling emergence rate was the fastest when the mean air temperature was about 18 ~C. Higher or lower air temperature would decrease the seedling emergence rate. The test cultivars had less difference in the days from seedling to jointing, which was slightly affected by air temperature. Compared with Danyu 39 and Yuandan 29, the late-maturing Longdan 13 had an increased growth rate from jointing to mature stage, and thus, the days for mature shortened markedly. For all the three maize cultivars, the days from jointing to mature tended to decrease with increasing air temperature. The dry matter accumulation rate in whole growth period, grain yield, and 100-seed mass were in the order of Danyu 39 〉 Yuandan 29 〉 Longdan 13.